1. Field of the Invention
The present invention relates to an optical element integrated module formed by integrating optical passive elements and optical active elements and more specifically to an optical element integrated module for modulating an optical short pulse train in accordance with an optical data signal.
2. Description of the Related Art
An optical element integrated module using a technology of modulating an optical short pulse train by utilizing an electrolyzation absorption effect of an EA (Electro-absorption) modulator has been disclosed in Japanese Patent Application Laid-open No. 2005-26725 or “160 Gbit/s Ultra-High-Speed Optical Time Division Multiple/Separation Technique Using EA-Modulator” written by Hitoshi Murai, O plus E, May 2005, vol. 27, No. 5, pp. 535-540 for example.
However, because in the technology described above the optical short pulse train are modulated by inputting a high frequency electrical signal to the EA modulator, it is necessary to provide an optical/electrical converter for converting an optical data signal into an electrical signal to obtain a high frequency electrical signal. Further, it is also necessary to provide an electrical circuit for inputting a high frequency electrical signal to the EA modulator. Therefore, the above-mentioned conventional art technology has a problem that its system configuration is complicated, and the cost of the apparatus is increased.